Synthesis of Boron Nitride Nanotubes Incorporated with Pd and Pt Nanoparticles for Catalytic Oxidation of Carbon Monoxide

Facile synthesis of Pd and Pt nanoparticles supported on the boron nitride nanotubes (Pd-BNNT and Pt-BNNT, respectively) for CO oxidation was explored. The reduction agent and stabilizer-free synthesis solely relies on the ultrasound treatment of the aqueous Pd²⁺ and Pt⁴⁺ precursors under the presence of BNNT. Reduction of Pd and Pt nanoparticles on the surface of BNNT was observed by means of the transmission electron microscopy and X-ray diffraction patterns. Quantitative analysis of Pd and Pt attached on the BNNT surface was also carried out using inductively coupled plasma atomic emission spectroscopy, showing that the concentration of metal nanoparticles on BNNT could be controlled by varying the initial concentration of metal precursors and the ultrasound treatment time. The morphological evolution of the nanoparticles on the surface of BNNT was observed by raising the temperature up to 800 °C in an air and up to 900 °C in vacuum. It was found that the nanoparticles were thermally stable up to 600 °C for both cases. The efficiency of catalytic oxidation of CO of the synthesized Pd-BNNT and Pt-BNNT was measured to be higher than ∼98% at the temperature as low as ∼125 and ∼150 °C, respectively.